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Leading Pattern of Spring Drought Variability over East Asia and Associated Drivers
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作者 赵庆红 杨崧 +1 位作者 田红瑛 邓开强 《Journal of Tropical Meteorology》 SCIE 2024年第1期1-10,共10页
Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their ... Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their leading variability and associated causes remain unclear.Based on the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis product from 1979 to 2020,this study evealuates the severity of spring droughts in East Asia and investigates their variations and associated drivers.The results indicate that North China and Mongolia have experienced remarkable trends toward dryness during spring in recent decades,while southwestern China has witnessed an opposite trend toward wetness.The first Empirical Orthogonal Function mode of SPEI variability reveals a similar seesawing pattern,with more severe dryness in northwestern China,Mongolia,North China,South Korea,and Japan but increased wetness in Southwestern China and southeast Asia.Further investigation reveals that the anomalously dry(wet)surface in North(Southwestern)China is significantly associated with anomalously high(low)temperature,less(more)precipitation,and reduced(increased)soil moisture during the previous winter and early spring,regulated by an anomalous anticyclone(cyclone)and thus reduced(increased)water vapor convergence.The spring dry-wet pattern in East Asia is also linked to cold sea surface temperature anomalies in the central-eastern Pacific.The findings of this study have important implications for improving the prediction of spring drought events in East Asia. 展开更多
关键词 DROUGHT leading pattern East Asia spring DRIVERS
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Research on Leading Edge Erosion and Aerodynamic Characteristics of Wind Turbine Blade Airfoil
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作者 Xin Guan Yuqi Xie +2 位作者 Shuaijie Wang Mingyang Li Shiwei Wu 《Fluid Dynamics & Materials Processing》 EI 2024年第9期2045-2058,共14页
The effects of the erosion present on the leading edge of a wind turbine airfoil(DU 96-W-180)on its aerodynamic performances have been investigated numerically in the framework of a SST k–ωturbulence model based on ... The effects of the erosion present on the leading edge of a wind turbine airfoil(DU 96-W-180)on its aerodynamic performances have been investigated numerically in the framework of a SST k–ωturbulence model based on the Reynolds Averaged Navier-Stokes equations(RANS).The results indicate that when sand-induced holes and small pits are involved as leading edge wear features,they have a minimal influence on the lift and drag coefficients of the airfoil.However,if delamination occurs in the same airfoil region,it significantly impacts the lift and resistance characteristics of the airfoil.Specifically,as the angle of attack grows,there is a significant decrease in the lift coefficient accompanied by a sharp increase in the drag coefficient.As wear intensifies,these effects gradually increase.Moreover,the leading edge wear can exacerbate flow separation near the trailing edge suction surface of the airfoil and cause forward displacement of the separation point. 展开更多
关键词 Wind energy wind turbine EROSION AIRFOIL leading edge erosion characteristics aerodynamic performance numerical simulation
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Exploring the Path of Party Building Leading League Construction in Colleges and Universities under the Pattern of Great Ideological and Political Education
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作者 Yi SHENG Tao LI 《Asian Agricultural Research》 2024年第5期42-46,共5页
In accordance with the pattern of"great ideology and politics",the Party and youth League organizations assume the role of vanguard in the organization of colleges and universities.Simultaneously,they serve ... In accordance with the pattern of"great ideology and politics",the Party and youth League organizations assume the role of vanguard in the organization of colleges and universities.Simultaneously,they serve as a pivotal force in ideological and political education.In order to construct a comprehensive ideological and political framework encompassing the entire educational process,it is of paramount importance to identify an efficacious methodology for Party building leading League construction.This paper employs a comprehensive analysis to elucidate the pivotal role of Party building leading League construction in facilitating ideological and political education.It also illuminates the practical challenges encountered in the implementation of Party building leading League construction initiatives within colleges and universities.The article proposes a specific path for Party building leading League construction in colleges and universities based on three key aspects:cohesion of the consensus of Party building leading League building,establishment of the institutional system of Party building leading League construction,and creation of the model brand of Party building leading League construction.The aim is to promote in-depth development of Party building in colleges and universities and enhance the quality and effect of ideological and political education. 展开更多
关键词 Great ideological and political education pattern Party building in universities and colleges Party building leading League construction
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Numerical Study on the Duct Noise Control of Single-Stage Axial Flow Fan with Wave Leading Edge Stator Blade Configurations 被引量:1
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作者 Jianxin Lian Hang Tong +2 位作者 Liangji Zhang Weiyang Qiao Weijie Chen 《Journal of Applied Mathematics and Physics》 2023年第8期2503-2514,共12页
This study focuses on a single-stage axial flow fan, investigating the effect of three kinds of wave leading edge stator blades on its noise reduction. The DDES method and the duct acoustic analogy theory based on the... This study focuses on a single-stage axial flow fan, investigating the effect of three kinds of wave leading edge stator blades on its noise reduction. The DDES method and the duct acoustic analogy theory based on the penetrable data surface were used for noise prediction. The results showed that the three kinds of wave leading edge blades were effective in reducing the rotor-stator interaction tonal noise and also have a certain inhibitory effect on broadband noise. The A10W15 stator blade can effectively reduce broadband noise in the frequency range of 2200 - 4200 Hz. When the amplitude is increased to 20, the noise reduction effect is further enhanced. However, when the amplitude is increased to 30, the broadband noise reduction effect is no longer significant. Further research shows that the wave leading edge stator blades can significantly change the pressure fluctuation distribution on the leading edge and suction surface, which control the modal energy distribution. Finally, this paper analyzed multiple factors affecting the broadband noise reduction, such as the noise source cut-off and cut-on effect and correlation. The purpose of this paper is to explore the laws of the influence of wave leading edge blades on the duct noise of real fan, and to reveal its noise control mechanism. . 展开更多
关键词 FAN Wave leading Edge Blade Duct Noise Broadband Noise Noise Source Analysis
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Dynamical Predictability of Leading Interannual Variability Modes of the Asian-Australian Monsoon in Climate Models 被引量:1
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作者 Lin WANG Hong-Li REN +2 位作者 Fang ZHOU Nick DUNSTONE Xiangde XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期1998-2012,I0002,I0003,共17页
The dynamical prediction of the Asian-Australian monsoon(AAM)has been an important and long-standing issue in climate science.In this study,the predictability of the first two leading modes of the AAM is studied using... The dynamical prediction of the Asian-Australian monsoon(AAM)has been an important and long-standing issue in climate science.In this study,the predictability of the first two leading modes of the AAM is studied using retrospective prediction datasets from the seasonal forecasting models in four operational centers worldwide.Results show that the model predictability of the leading AAM modes is sensitive to how they are defined in different seasonal sequences,especially for the second mode.The first AAM mode,from various seasonal sequences,coincides with the El Niño phase transition in the eastern-central Pacific.The second mode,initialized from boreal summer and autumn,leads El Niño by about one year but can exist during the decay phase of El Niño when initialized from boreal winter and spring.Our findings hint that ENSO,as an early signal,is conducive to better performance of model predictions in capturing the spatiotemporal variations of the leading AAM modes.Still,the persistence barrier of ENSO in spring leads to poor forecasting skills of spatial features.The multimodel ensemble(MME)mean shows some advantage in capturing the spatiotemporal variations of the AAM modes but does not provide a significant improvement in predicting its temporal features compared to the best individual models in predicting its temporal features.The BCC_CSM1.1M shows promising skill in predicting the two AAM indices associated with two leading AAM modes.The predictability demonstrated in this study is potentially useful for AAM prediction in operational and climate services. 展开更多
关键词 Asian-Australian monsoon(AAM) leading interannual variability modes El Niño seasonal forecasting models multimodel ensemble(MME)
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Research on the Evolution of Media Practices of Leading Cadres’ New Media and the Communication Characteristics
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作者 Hebin Zhang Muhammad Zaffwan Idris 《Social Networking》 2023年第3期57-66,共13页
Purpose/Significance: This study aims to define the concept of leading cadres new media usage in China specifically, and to describe and analyze the forms and typical cases and characteristics of leading cadres new me... Purpose/Significance: This study aims to define the concept of leading cadres new media usage in China specifically, and to describe and analyze the forms and typical cases and characteristics of leading cadres new media in different stages. Method/Process: Based on the themes and contents of a few media accounts of leading cadres at different ranks, we summarizes leading cadres new media usage in a systematic perspective and content analysize method. Result/Conclusion: The study defines the concept of Leading Cadres’ new media from the perspective of media practice, determine its position as a media communication platform in the government affairs new media communication system and its relationship with the other elements, and then systematically review the evolution of its media practice from personal website, blog, microblog and microblog to WeChat, live show. On this basis, with the Harold Lasswell communication model, this article summarizes leading cadres new media communication characteristics from five aspects: content producer, content, channel, audience, and effect. Future studies may also enhance the empirical research from the effect perspective. 展开更多
关键词 leading Cadres’ New Media Evolution of Media Practices Communication Characteristics
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MiR-107-3p/Atp6v0e1 contributes to protective effects of two selenium-containing peptides,TSeMMM and SeMDPGQQ on lead-induced neurotoxicity
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作者 Yong Fang Tianhang Huang +5 位作者 Jian Wu Xieqi Luo Fengjiao Fan Peng Li Jian Ding Xinyang Sun 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2060-2067,共8页
Two selenium(Se)-containing peptides from Se-enriched rice,TSeMMM and SeMDPGQQ,possess neuroprotective potency against lead(Pb2+)-induced cytotoxicity.However,the crosstalk between mRNA and microRNAs(miRNA)involved in... Two selenium(Se)-containing peptides from Se-enriched rice,TSeMMM and SeMDPGQQ,possess neuroprotective potency against lead(Pb2+)-induced cytotoxicity.However,the crosstalk between mRNA and microRNAs(miRNA)involved in the neuroprotection mechanism remains to be elucidated.In this study,RNA-sequencing and miRNA-sequencing were used to independently identify differentially expressed mRNAs and small RNAs profiles in Pb^(2+)-treated primary fetal rat cortical neurons and then the correlated miRNA-mRNA target pairs were obtained.It was found that 34 mRNAs related to oxidative phosphorylation could be reversed by pretreatment of TSeMMM and SeMDPGQQ.The protective effect of TSeMMM and SeMDPGQQ was mediated by upregulation of miR-107-3p,which downregulates the ATPase H+transporting V0 subunit e1(Atp6v0e1)mRNA level.A zebrafish model was applied to verify the relevance between the targeted mRNA and miRNA by real-time quantitative PCR.The results indicated that miR-107-3p was a potential therapeutic target to achieve neuroprotection of Se-containing peptides via stimulation of Atp6v0e1. 展开更多
关键词 lead Se-containing peptides NEUROPROTECTION miRNA
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A short overview of the lead iodide residue impact and regulation strategies in perovskite solar cells
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作者 Eng Liang Lim Zhanhua Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期504-510,I0012,共8页
Lead iodide(PbI2) is a vital raw material for preparing perovskite solar cells(PSCs),and it not only takes part in forming the light absorption layer but also remains in the grain boundary as a passivator.In other wor... Lead iodide(PbI2) is a vital raw material for preparing perovskite solar cells(PSCs),and it not only takes part in forming the light absorption layer but also remains in the grain boundary as a passivator.In other words,the PbI2 content in the precursor and as formed film will affect the efficiency and stability of the PSCs.With moderate residual PbI2,it passivates the bulk/surface defects of perovskite,reduces the interfacial recombination,promotes the perovskite stability,minimizes the device hysteresis,and so on.Deficient PbI2 residue will reduce the interfacial passivation effect and device performance.In addition to facilitating the non-radiative recombination,over PbI2 residue can also lead to electronic insulation in the grain boundary and deteriorate the device performance.However,the impact and regulation of PbI2 residue on the device performance and stability is still not fully understood.Herein,a comprehensive and detailed review is presented by discussing the PbI2 residue impact and its regulation strategies(i.e., elimination,facilitation and conversion of the residue PbI2) to manipulate the PbI2 content,distribution and forms.Finally,we also show future outlooks in this field,with an aim to help further the progression of high-efficiency and stable PSCs. 展开更多
关键词 lead iodide RESIDUE REGULATION Perovskite solar cells Efficiency Stability
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Epicatechin attenuates lead(Pb)-induced cognitive impairment in mice:regulation on Nrf2 signaling pathway,and interference on the interaction between Pb with albumin
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作者 Dai Cheng Qianqian Yu +2 位作者 Kexin Zhu Dingdong Bu Zijian Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1065-1078,共14页
Epicatechin(EC)was used in this study to antagonize the cognitive dysfunction caused by lead(Pb)exposure in mice.Eight-week-old male Kunming mice were treated with PbCl_(2)(20 mg/kg)and/or EC(50 mg/kg)by gavage admini... Epicatechin(EC)was used in this study to antagonize the cognitive dysfunction caused by lead(Pb)exposure in mice.Eight-week-old male Kunming mice were treated with PbCl_(2)(20 mg/kg)and/or EC(50 mg/kg)by gavage administration for 4 weeks.Morris water maze test showed that EC could improve memory dysfunction induced by Pb.EC antagonized Ca^(2+)overload,activated Nrf2 signaling pathway and reduced the accumulation of Pb in the brain and serum,which suggested that EC might alter Pb distribution in mice.In vitro,spectroscopic analysis,potentiometric titration and docking studies were applied to inquiry into the interaction between bovine serum albumin(BSA)and Pb^(2+)in presence or absence of EC.EC was proved to chelate Pb^(2+)and reduced the interaction between BSA and Pb^(2+).In summary,EC might protect Pb-induced cognitive impairment by activating Nrf2 signaling pathway,and suppressing Pb accumulation via interference on the binding of Pb to albumin. 展开更多
关键词 lead EPICATECHIN Bovine serum albumin Interaction Oxidative stress
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In-situ defect passivation assisted three-step printing of efficient and stable formamidine-lead bromide solar cells
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作者 Hang Yang Tao Zhou +6 位作者 Haoyu Cai Wenjian Shen Hao Chen Yongjun Liu Juan Zhao Yi-Bing Cheng Jie Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期396-405,共10页
Perovskite solar cells(PSCs)emerge as the most promising photovoltaics(PV)for their high performance and potential convenient cost-effective production routes comparing to the sophomore PV technologies.The printed PSC... Perovskite solar cells(PSCs)emerge as the most promising photovoltaics(PV)for their high performance and potential convenient cost-effective production routes comparing to the sophomore PV technologies.The printed PSCs with simplified device architecture and fabrication procedures could further enhance the competitive strength of PSC technology.In this work,we present an in-situ defect passivation(ISDP)assisted full-printing of high performance formamidine-lead bromide(FAPbBr_(3))PSCs.Only three rapid printing steps are involved for electron transporting layer(ETL),perovskite and carbon to form a complete solar cell on the low-cost fluorine-doped tin oxide(FTO)substrate.Long-chain polymer monomethyl ether polyethylene glycol is particularly utilized as the ISDP passivator,leading to conformal coating on the rough FTO and defect passivation for both ETL and perovskite during printing.A high efficiency of 10.85%(certified 10.14%)and a high V_(oc)up to 1.57 V are achieved for the printed device.The unencapsulated PSCs maintain above 90%of the initial efficiency after continuously heating at 85℃for 1000 h and over 80%of the efficiency after the maximum power point tracking for 3500 h.The fully printed semitransparent PSCs with carbon grids(CGs)show average visible light transmittance over 33%and an efficiency of 8.81%. 展开更多
关键词 Formamidinium lead bromide Fully printed Lowcosts Carbon electrode SEMITRANSPARENT
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Universal Encapsulation Adhesive for Lead Sedimentation and Attachable Perovskite Solar Cells with Enhanced Performance
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作者 Xuehao Zhu Haoyu Cai +7 位作者 Cong Bai Zhengzhe Wu Wenjian Shen Yiming Xiong Juan Zhao Fuzhi Huang Yibing Cheng Jie Zhong 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期303-310,共8页
In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-h... In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-heal within 45 min at room temperature with an efficient lead ion-blocking rate of 99.3%.The PUA film can be coated on a metal electrode with slight efficiency improvement from 23.96%to 24.15%.The thermal stability at 65℃and the humidity stability at 55%relative humidity(RH)are superior to the devices encapsulated with polyisobutylene.The PUA film has strong adhesion to the flexible substrate and the initial efficiency of the flexible perovskite module(17.2%)encapsulated by PUA remains 92.6%within 1825 h.These results suggest that PUA encapsulation is universal for rigid and flexible PSCs with enhanced stability and low lead hazards.Moreover,it was found that flexible PSCs can be well attached to various substrates with PUA,providing a facile route for the A-PSCs in various scenarios without additional encapsulation and installation. 展开更多
关键词 ADHESIVE attachable device flexible module lead leakage POLYURETHANE
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Seismic evaluation of frequency influence and resonant behavior for lead rubber bearing isolated rigid rectangular liquid tanks
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作者 Jyoti Ranjan Barik Kishore Chandra Biswal 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期973-994,共22页
The seismic behavior of a partially filled rigid rectangular liquid tank is investigated under short-and longduration ground motions.A finite element model is developed to analyze the liquid domain by using four-noded... The seismic behavior of a partially filled rigid rectangular liquid tank is investigated under short-and longduration ground motions.A finite element model is developed to analyze the liquid domain by using four-noded quadrilateral elements.The competency of the model is verified with the available results.Parametric studies are conducted for the dynamic parameters of the base-isolated tank,using a lead rubber bearing to evaluate the optimum damping and time period of the isolator.The application of base isolation has reduced the total and impulsive hydrodynamic components of pressure by 80 to 90 percent,and base shear by 15 to 95 percent,depending upon the frequency content and duration of the considered earthquakes.The sloshing amplitude of the base-isolated tank is reduced by 18 to 94 percent for most of the short-duration earthquakes,while it is increased by 17 to 60 percent for the majority of the long-duration earthquakes.Furthermore,resonance studies are carried out through a long-duration harmonic excitation to obtain the dynamic behavior of non-isolated and isolated tanks,using a nonlinear sloshing model.The seismic responses of the base-isolated tank are obtained as higher when the excitation frequency matches the fundamental sloshing frequency rather than the isolator frequency. 展开更多
关键词 lead rubber bearing frequency domain resonant inputs long-duration excitation
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Conformity Assessment of Lead Aprons Used in Conventional Radiology: A Multi-Centre Survey in Togo
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作者 Massaga Dagbé Bidamin N’timon +8 位作者 Ousmane Aminata Bah Pihou Gbandé Komi Awobanou Koku Adambounou Masamaesso Tchaou Abdoulatif Amadou Lantam Sonhaye Lama Kegdigoma Agoda-koussema Komlanvi Victor Adjénou 《Open Journal of Radiology》 2024年第2期55-63,共9页
Aim: Lead aprons are used to protect against scattered radiation from the patient during interventional procedures and certain special conventional radiological examinations. Given the importance of the role lead apro... Aim: Lead aprons are used to protect against scattered radiation from the patient during interventional procedures and certain special conventional radiological examinations. Given the importance of the role lead aprons are supposed to play in radiation protection, we propose to assess their conformity in medical imaging departments in public and religious hospitals in Togo. Materials and method: A multi-centre survey conducted from 26 November to 06 December 2021 in the radiology departments of public and religious health facilities in Togo. All aprons in use were included. The evaluation criteria were physical (visual), quantitative (radiographic) and qualitative (dosimetric). Results: We had registred 43 aprons among wich 27 (62.79%) leaded aprons were labelled non-compliant and 16 (37.21%) were labelled compliant. Of the aprons judged to be non-compliant, 70.37% were more than 10 years old and 96.30% showed defects on the radiographic images. The most common defects were vampire marks (18.64%), multiple folds (16.96%), cracks (16.96%), multiple cracks (15.25%), tears (8.47%), absence of lead (5.08%), holes (3.39%) and lead corrosion (1.69%). Defective aprons (62.96%) had at least two defects. The defects were of thoraco-abdomino-pelvic (74.07%), thoracic (14.82%) and abdomino-pelvic (11.11%) topography. For indirect exposure at 50 and 70 kilovolts, all the aprons had an attenuation factor greater than 90%. After dosimetric measurement, 13.95% of aprons had attenuation factors below 90% for indirect exposure at 100 kilovolts. Conclusion: The compliance of the leaded decks is trifactorial (physical, radiographic and dosimetric). However, there is no significant difference in X-ray attenuation capacity between defective and normal decks. 展开更多
关键词 lead Apron Compliance Radiation Protection RADIOLOGY TOGO
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Management of a patient with an unusual trajectory of a temporary trans-venous pacing lead
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作者 Metesh Acharya Ethan Kavanagh +2 位作者 Sheena Garg Davorin Sef Fabio De Robertis 《World Journal of Cardiology》 2024年第6期314-317,共4页
Perforation of the right ventricle during placement of pacing wires is a welldocumented complication and can be potentially fatal.Use of temporary pacemaker,helical screw leads and steroids use prior to implant are re... Perforation of the right ventricle during placement of pacing wires is a welldocumented complication and can be potentially fatal.Use of temporary pacemaker,helical screw leads and steroids use prior to implant are recognised as risk factors for development of post-permanent pacemaker effusion.We reported an unusual case of pacing wire perforating interventricular septum into the left ventricle that occurred during the implant procedure performed in another institution.After the preoperative work-up and transfer to our tertiary cardiothoracic centre,the patient underwent successful surgical management.In conclusion,early recognition and timely diagnosis using advanced multimodality imaging can guide surgical intervention and prevent unfavourable consequences of device-related complications. 展开更多
关键词 Ventricular perforation lead perforation PACING
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Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region
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作者 Qiuyan DU Chun ZHAO +6 位作者 Jiawang FENG Zining YANG Jiamin XU Jun GU Mingshuai ZHANG Mingyue XU Shengfu LIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期801-816,共16页
Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality forecasts.However,the particular impact of meteorological foreca... Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality forecasts.However,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well known.In this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are investigated.With increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal variations.In general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary particles.In spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural dust.In summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation rate.In autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation. 展开更多
关键词 PM_(2.5) forecasting uncertainties forecast lead time meteorological fields Beijing-Tianjin-Hebei region
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Analysis of Oxygen Consumption in Lead and Zinc Metallurgy
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作者 Lun Sheng Pengpeng Zhang 《Frontiers of Metallurgical Industry》 2024年第2期5-9,共5页
This article analyzes the role of oxygen in lead zinc metallurgy,including shortening the metallurgical process,promoting energy conservation and environmental protection,improving metallurgical strength,enhancing raw... This article analyzes the role of oxygen in lead zinc metallurgy,including shortening the metallurgical process,promoting energy conservation and environmental protection,improving metallurgical strength,enhancing raw material adaptability,and enhancing comprehensive recovery efficiency.This article introduces different lead zinc metallurgical processes and their oxygen consumption characteristics,including oxygen enriched side blowing lead smelting,oxygen bottom blowing lead smelting,oxygen enriched top blowing lead smelting,flash smelting lead,oxygen pressure leaching zinc smelting,and atmospheric pressure oxygen leaching zinc smelting.It is pointed out that oxygen enhanced metallurgy is the direction for the transformation and upgrading of lead zinc metallurgy. 展开更多
关键词 lead zinc metallurgy oxygen rich smelting oxygen pressure leaching energy conservation and emission reduction
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MER联合Lead-DBS在帕金森病患者术后程控中的应用研究
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作者 刘明辉 杨新超 +2 位作者 路小奇 田海港 郭效东 《临床研究》 2024年第7期11-14,共4页
目的探讨微电极记录(MER)联合多模态影像融合技术(Lead-DBS)多模态影像融合技术在帕金森病患者术后程控中的应用效果。方法选取中国人民解放军联勤保障部队第九八八医院2018年10月至2023年8月期间收治的60例帕金森病患者,随机将其分为... 目的探讨微电极记录(MER)联合多模态影像融合技术(Lead-DBS)多模态影像融合技术在帕金森病患者术后程控中的应用效果。方法选取中国人民解放军联勤保障部队第九八八医院2018年10月至2023年8月期间收治的60例帕金森病患者,随机将其分为对照组和观察组。对照组患者根据脑深部电刺激术(DBS)专家程控共识逐个触点程控,观察组患者根据MER联合术后Lead-DBS多模态影像融合技术进行程控。比较两组术中操作时间、术后症状改善情况、生活质量评分、不良情绪及并发症发生率。结果观察组术中操作时间少于对照组,差异具有统计学意义(P<0.05);干预前两组帕金森症状评分、帕金森病生活质量评分、不良情绪评分、并发症发生率差异均无统计学意义(P>0.05),干预后观察组帕金森症状评分、帕金森病生活质量评分、不良情绪评分、并发症发生率均低于对照组,差异均有统计学意义(P<0.05)。结论术中MER联合术后Lead-DBS多模态影像融合技术,结合患者症状针对性选择开机触点方法具有较高的可行性,可提高手术效率、改善患者预后,安全性良好。 展开更多
关键词 MER lead-DBS 帕金森病 术后程控
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Mechanical and Electrical Properties of Some Sn-Zn Based Lead-Free Quinary Alloys
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作者 Shihab Uddin Md. Abdul Gafur +1 位作者 Suraya Sabrin Soshi Mohammad Obaidur Rahman 《Materials Sciences and Applications》 2024年第7期213-227,共15页
Although there are many lead-free soldering alloys on the market, none of them have ideal qualities. The researchers are combining binary alloys with a variety of additional materials to create the soldering alloys’ ... Although there are many lead-free soldering alloys on the market, none of them have ideal qualities. The researchers are combining binary alloys with a variety of additional materials to create the soldering alloys’ features. The eutectic Sn-9Zn alloy is among them. This paper investigated the mechanical and electrical properties of Sn-9Zn-x (Ag, Cu, Sb);{x = 0.2, 0.4, and 0.6} lead-free solder alloys. The mechanical properties such as elastic modulus, ultimate tensile strength (UTS), yield strength (YS), and ductility were examined at the strain rates in a range from 4.17 10−3 s−1 to 208.5 10−3 s−1 at room temperature. It is found that increasing the content of the alloying elements and strain rate increases the elastic modulus, ultimate tensile strength, and yield strength while the ductility decreases. The electrical conductivity of the alloys is found to be a little smaller than that of the Sn-9Zn eutectic alloy. 展开更多
关键词 lead-Free Solder Strain Rate Ultimate Tensile Strength DUCTILITY Electrical Conductivity
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The Study on Innovation Model Characteristics and Function Enhancement of “Leading Grain Enterprises+Farmers” in New Circumstances——an Investigation and Analysis on Major Grainproducing Areas in Hubei Province 被引量:1
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作者 曾靖 《Agricultural Science & Technology》 CAS 2016年第12期2896-2900,共5页
ln the context of comprehensively deepening the reform, and integration of three The first, second and third industry sectors in rural areas, the research took major grain-producing areas in Hubei as an example, analy... ln the context of comprehensively deepening the reform, and integration of three The first, second and third industry sectors in rural areas, the research took major grain-producing areas in Hubei as an example, analyzed dominant grain in-dustrialization models “leading grain enterprises+farmers”, and revealed its character-istics, advantages, and approaches for function reinforcement. The research is so meaningful, practical y or in future. 展开更多
关键词 Major grain-producing area leading grain enterprises FARMERS Linkage organization lnnovation model
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Resistance Evaluation of Part of Leading Rice Varieties to Rice Blast in Guangxi Province
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作者 颜群 罗志勇 +3 位作者 张晋 高利军 陈小林 高汉亮 《Agricultural Science & Technology》 CAS 2015年第3期518-522,共5页
In order to determine the resistance of leading rice varieties to rice blast in Guangxi, three natural induction rice blast nurseries were established in Cenxi, Sanjiang and Yongfu. The resistance of the 45 leading ri... In order to determine the resistance of leading rice varieties to rice blast in Guangxi, three natural induction rice blast nurseries were established in Cenxi, Sanjiang and Yongfu. The resistance of the 45 leading rice varieties in Guangxi to rice blast was determined under conditions of spray inoculation and natural induction at seedling stage. The results showed that resistance frequencies of the 45 leading rice varieties ranged from 8.33% to 94.44%. Among the 45 tested varieties, there were 8 varieties of which the resistance frequencies were all higher than 80%, accounting for 17.78%; there were 11 varieties of which the resistance frequencies ranged from 50% to 80%, accounting for 24.44%; the resistance frequencies of the remaining varieties were all lower than 50%, accounting for 57.78% of the total tested varieties. The twoconsecutive-year determination results showed none of the 45 leading rice varieties showed resistance to rice blast. In 2010, there were 26, 12 and 7 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 57.78%, 26.67% and 15.56% of the total tested varieties. In 2011, there were 16, 23 and 12 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 35.56%, 51.11% and 13.33%. The overall resistance of the 45 leading rice varieties trended to be decreased year by year. So in rice production, they should be selected properly. 展开更多
关键词 leading rice varieties Rice blast Resistance evaluation GUANGXI
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